Clamping means for rail structures



Sept. 22, 1959 L. BLUM CLAMPING MEANS FOR RAIL STRUCTURES Filed Feb. 8, 1956 INVENTOR.

United States Patent G i CLAMPING MEANS FOR RAIL STRUCTURES Louis Blum, Pittsburgh, Pa., assignor to Blumcraft of Pittsburgh, Pittsburgh, Pa., a firm This invention relates to new and useful improvements in ornamental rail structures, more particularly to im- I provements in the mounting brackets and posts for supporting hand rails.

It is among the objects of the invention to provide an ornamental rail structure consisting of hollow extruded aluminum of dovetail shape having a reenforced base wall designed to receive the ends of mounting bolts and to resist the strains imposed by locking the mounting bolts to said base walls.

Another object of the invention is to provide an ornamental rail structure in which the rail and posts are constructed of a hollow extruded shape designed to serve the purpose of both post and rail with simple clamping means for mounting the rail on the post.

It is still another object of the invention to provide clamping means for ornamental rails in which a resilient element is disposed between the rail clamping members to eliminate binding when the clamping elements are drawn up in clamping engagement with the rail.

The invention will become more apparent from a consideration of the accompanying drawing constituting a part hereof in which like reference characters designate like parts and in which:

Figure l is a vertical cross-sectional view of the upper portion or top rail of an ornamental rail structure mounted on a post;

Figure 2, a similar view of an intermediate or bottom rail mounted on the same post as the rail of Figure 1;

Figure 3, a transverse cross-sectional view taken along the line 33, Figure 2;

Figure 4, an isometric view, partially cut away, of an ornamental rail structure embodying the elements of Figures 1 to 3 of the drawing; and

Figure 5 is an end elevational view of a portion of the rail clamp as will be hereinafter explained.

In the drawing, the numeral 1 designates a rail post and the numeral 2 a rail, the post as shown in the transverse section of Figure 3 being of the same dimensions and design as the rail 2 of Figure 1. Such similarity in the rail and post structure is desirable because a single extruded shape can be readily cut to length as posts and rails, and fitted with ornamental end pieces, such as the members 3 and 4, Figure 4, to produce an inexpensive yet pleasing ornamental rail structure.

In accordance with the present invention, the extruded element from which the posts and rails 1 and 2 are cut is provided with a heavy reenforced base 5 with a central V portion 6 for centering the clamping element such as the member 7, Figures 2 and 3. Also the heavy base section 5 prevents collapse of the dovetail shape rail 2 when subjected to the clamping action of clamp members 8 and 9 between which the rail 2 is held.

The clamps 8 and 9 are of cylindrical shape, as shown in Figure 5, and are provided with dovetail slots 10 for receiving the base of the rail 2. The members 8 and 9 are provided with tongues 11 and grooves 12, respectively, with a rubber washer 13 disposed therebetween. As

I 2,905,446 Patented Sept. 22, 1959.

shown in Figure 5, the cutout dovetail portion 10 may cut away a portion of the tongue and groove of the clamps and in such case a rubber gasket or washer 13 of corresponding dimensions is employed instead of a full washer; The clamps 8 and 9 are provided with central bores 14 and 15, respectively, and bores 16 and 17 with intermediate ribs or shoulder portions 18 and 19. Disposed in the cylindrical portion 14 and 15 is a sleeve.20 having screw threaded portions for receiving the threaded ends21 and 22 of screws or shanks 23 and 24, respectively. Screw 23 has a head that fits into the recess 16 of clamp' 8 and screw shank 24 is provided with a ring nut 25 by which the screw can be locked against the shoulder 19 of clamp 9. The screw shank 24 is provided with a head portion 26 having a flat tongue 27, Figure 3, that fits into slot 28 of the element 7 that is connected by a pin 29 to pivot on the tongue 27.

In the mounting of the ornamental rails, holes designated by the numeral 30, Figure 2, are drilled through the reenforced heavy base section 5 of the extruded post 1 and the end piece 7, which is in alignment with the screw shank 24, is passed through the opening 30 into the hollow chamber of the post. The element 7 is then upset by pushing it against the end wall of the post opposite the perforation 30 to be at right angles to the screw shank 24, as shown in Figures 2 and 3. The portion 7 rests in the V 6 of the wall 5 of the post as shown in Figure 3, and provides a relatively large area of contact of the clamp with the post to distribute the clamping strain.

The clamping element 9 is slipped over the screw shank 24 and screw sleeve 20 is threaded on the thread 22 of screw shank 24 until it abuts the shoulder 19 of the clamp 9. The rubber washer 13 is placed in the groove 12 of clamp 9 and the clamp portion 8 is slipped on sleeve 20 with the tongue 11 disposed in slot 12 and abutting the rubber ring 13. Screw 23 is threaded into sleeve 20 with the head portion abutting the shoulder 18 to draw the clamping element 8 into clamping engagement with the rail 2.

It will be noted that the assembly of the one-half of the clamp element 9 with the screw sleeve 20 is eiiected and thereby the clamping element 7 is firmly drawn against the V base of the upright or post 1 independently of the clamping action of the clamp 8, so that the clamping strain is not alone imposed on the threaded portion 21 of the screw 23.

I have found that the rubber washer 13 eliminates tilting or misalignment of the clamping elements 8 and 9 so that uniform clamping pressure is brought to bear upon the dovetail shape rail 2 when the clamping element 8 is drawn tight against the clamping element 9. Also, by means of the upsettable end 7 of the screw shank 24 and the heavy reenforced V-shape base wall of the extruded element 1, the stresses are distributed over a relatively large clamping area which prevents breaking or distortion of the metal.

As shown in Figure l, the top of the post 1 is provided with an end bracket 3 having a threaded portion for receiving the threaded end 31 of a screw shank which, in other respects, is like the member 24 of Figure 2 and the structure when assembled is of the general appearance of Figure 4.

Although one embodiment of the invention has been herein illustrated and described, it will be evident to those skilled in the art that various modifications may be made in the details of construction without departing from the principles herein set forth.

I claim:

1. In an ornamental rail structure a hollow bar of substantially dovetail shape cut in lengths for posts and rails and joined by clamping brackets mounted in the posts for securing the rails, said hollow bar having a base wall of substantially greater thickness than its other walls at the wide portion of its dovetail body with the inner surface thereof shaped to'form a V for centering the rail mounting brackets, a clainp for mountingtthe rails on saidposts consisting of a threaded shank having a head pivotally mounted at one end for insertion in an opening in the thick wall of the posts, said head being of a shape to rest in the centering V of said post wall when drawn against the post. p

m 2.' In an ornamental rail structure a hollow bar of substantially dovetail shape cut to lengths for posts and rails and joined by clamping brackets mounted in the posts for securing the rails, said hollow bar having a base wall of substantially greater thickness than the other walls at the wide portion of its dovetail body with the inner surface thereof shaped to form a V for centering the:rail mounting brackets; a clamp for mounting the rails on'said posts consisting of a threaded shank having a head pivotally mounted at one end for insertion in an openingin the thick wall of the posts, said head being of a shape to rest in the centering V of said post wall when at right angles to said shank, a pair of split cylindrically shaped clamping members having inwardly extending radial flanges mounted on said shank and having dovetail shaped cut-out portions for receiving the wide base portion of said dovetail shaped rails and means engaging the flanges of said pair of splitclamping members for drawingthe split members into clamping engagement with said rail. 5

References Cited in the file of this patent UNITED STATES PATENTS 450,127 Wrigley Apr. 7, 1891 1,631,831 Palmer-Jones June 7, 1927 1,864,159 Williams June 21, 1932 2,431,546 Edwards Nov. 25, 1947 2,476,863 Hawes July 19, 1949 2,520,3I4 1 Harris Aug. 29, 1950 2,557,002" Lothrop June 12, 1951 Bush Apr. 1, 1952 

